The jury in the trial of Chris Huhne's ex-wife has retired to consider its verdict.

Vicky Pryce is charged with perverting the course of justice by taking her disgraced ex-husband's speeding points in 2003.

Jurors at Southwark Crown Court in London heard the economist denies the charge, claiming she was coerced by Huhne as he tried to avoid losing his licence.

The former energy secretary pleaded guilty to the offence last Monday, resigning as an MP, and now faces jail.

Concluding his summing up of the case, Mr Justice Sweeney told the jury of eight women and four men: ''It is of course for the prosecution to prove that Ms Pryce's will was not overborne in the sense that I have directed you.

''The prosecution say that you can be sure that her will was not overborne because either: one, the claim of coercion is invented, or two, she has lied about it, which she can only have done because it is false.

''Three, she has exaggerated what was really no more than persuasion by comparison between what she has said in the past and what she has said now, with now said to be an exaggeration.

''And fourthly, even on her own account in the witness box, the prosecution say, her will was not overborne, she simply made a choice for her own purposes and only got found out because she decided to use it as a weapon against Huhne.''

He said the prosecution said they had proved that marital coercion did not apply and so the correct verdict would be guilty.

He went on: ''The defence say that is all completely wrong.

''You should accept Ms Pryce's evidence about what happened as she has given it on oath before you, as being true.

''And that the result therefore should be that if you accept it is true, or even that it may be true, then the prosecution will have failed to make you sure either that Mr Huhne wasn't there when she signed the form, or that her will was not overborne.

''And in that event the defence say obviously the proper verdict is one of not guilty.''

The charges date back to 2003 when Huhne's BMW was clocked speeding on the way back from Stansted Airport. He was then an MEP and was travelling back from Strasbourg.

With nine points on his licence, he faced a driving ban and was worried it would affect his chances of being nominated as the Lib Dem candidate for the Eastleigh seat, which he went on to win in 2005.

Pryce, who had a clean licence at the time, claims her then husband forced her to take the points, saying if he lost his licence he risked not being nominated, which would be her fault.

She described him standing in their hallway ''waving'' a pen at her, presenting her with a ''fait accompli'', leaving her no choice but to sign.

Huhne was banned later that year for a different offence, the court heard.

The points-swapping allegations became public in May 2011 when they were published in national newspapers.

The court heard Pryce was speaking to journalists for months before that, as she tried to reveal the scandal in revenge for Huhne leaving her the previous year for PR adviser Carina Trimingham.

The prosecution claimed Pryce tried to ''peddle'' a false story to the Mail on Sunday in late 2010, claiming Huhne bullied a constituency aide into taking the points, and when that did not work, she revealed the points-swapping to Sunday Times political editor Isabel Oakeshott in March 2011, planning to ''nail'' the politician and trying unsuccessfully to record him confessing.

The story ran in both newspapers on May 8, 2011, sparking a police investigation and in February last year, Huhne and Pryce were charged with perverting the court of justice.

Then energy secretary Huhne was forced to step down from the Cabinet and vowed to fight the charges.

But he dramatically changed his plea on the first day of the trial last Monday, ending his political career.

During the trial, mother-of-five Pryce described how ''arrogant'' Huhne always wanted his own way.

He twice demanded she have an abortion when she fell pregnant accidentally, something she acquiesced to in 1990, then resisted two years later, giving birth to their youngest child.

Huhne left Pryce in June 2010 during half-time of a World Cup football match, confessing to an 18-month affair which was about to be exposed and ending their 26-year marriage.

Pryce, 60, of Crescent Grove, Clapham, south London, has adopted the defence of marital coercion - only available to wives when their will is ''overborne'' by their husband, who has to be physically present.

Her barrister argued that although successful, Pryce was not always capable of resisting her husband, and in 2010 when she revealed the scandal, she was ''fragile'' in the wake of their break-up.

But the prosecution claimed Pryce invented the account after the event in an effort to protect herself from punishment, accusing her of ''barefaced'' lies to the jury, and said she was strong enough to resist his bullying on some occasions.

Yesterday jurors were urged by Justice Sweeney: ''What is required of you is a cool, calm, careful and dispassionate consideration of the evidence together with the courage to return a true verdict whatever the consequences may be.''